Radio frequency (RF) devices such as network switches, wireless access points, ports and radio frequency identification (RFID) systems are becoming more commonplace in today's society with the market adoption of wireless local area network (WLAN) technologies. One criterion for the design of a WLAN network using RF devices is the RF coverage area for each device. In a typical design, the collective RF coverage areas of the RF devices facilitate effective communication by client devices. It is well understood that RF waves are susceptible to signal loss when passing through various physical and environmental factors. For example, the presence of doors, windows, walls, furniture, and shelving, are obstacles to the RF signal.
RF coverage maps provide graphical information about the coverage of various RF devices. RF coverage maps are useful for assessing the area for sufficient WLAN service and are typically derived from manual site surveys and mathematical modeling techniques. Some methods generate RF coverage maps based on received signal strength values associated with transmission signals exchanged between a wireless node and one or more wireless access points. Received signal strength values may be obtained at various locations to generate a coverage map for the wireless access points.
RF coverage maps may also be generated by estimation algorithms using, for example, path-loss models and ray tracing, in which RF devices are layered onto a plane. Two-dimensional models in the RF coverage maps may be floor-specific, providing visualizations of the coverage by RF devices that are physically placed on the floor being modeled. In many WLAN deployments, such as in a multi-floor building, the signal coverage may have presence beyond the floor boundaries, thereby making accurate coverage maps difficult to produce. Three-dimensional (3D) coverage maps may be more accurate but are computationally expensive.